Subtract 4/21 from 3/40
3/40 - 4/21 is -97/840.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
3/40 = 3 × 21/40 × 21 = 63/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
4/21 = 4 × 40/21 × 40 = 160/840 - Subtract the two like fractions:
63/840 - 160/840 = 63 - 160/840 = -97/840
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